Long-wall mining apparatus

ABSTRACT

An elongated conveyor is to extend along a mine face and has a bottom, one longitudinal side facing towards and another longitudinal side facing away from the mine face. An elongated casing is mounted on the conveyor at the other side thereof and extends along the conveyor upwardly of the bottom. The casing has two vertically spaced longitudinally extending cylindrical guide tracks each formed with a longitudinal slot at a side of the casing. Mounting members are spaced along the casing and each fixedly embraces the respective guide track. A ground-engaging support structure is carried by the mounting members and projects downwardly of the bottom adjacent the casing. An endless reciprocating drive chain having an upper and a lower run is received in the respective guide tracks, and a coal plough is located at the aforementioned one side of the conveyor and has a rigid connecting portion which extends beneath the bottom face to the casing and is connected with the one run of the chain so that the connecting portion and the coal plough are reciprocated lengthwise of said conveyor when the chain reciprocates in the guide tracks. The connecting portion is in part relieved of the weight of the conveyor and casing due to the ground-engagement by the support structure.

[451 July 29,1975

United States atent [191 Krohm et al.

[57] ABSTRACT An elongated conveyor is to extend along a mine face LONG-WALL MINING APPARATUS Inventors: Reinhold Krohm, Herne; Karl Bahre, Gladbeck, both of Germany and has a bottom, one longitudinal side facing towards and another longitudinal side facing away from the [73] Assignee: Klockner-Werke AG, Duisburg,

mine face. An elongated casing is mounted on the Germany conveyor at the other side thereof and extends along the conveyor upwardly of the bottom. The casing has two vertically spaced longitudinally extending cylindri- 22 Filed: Oct. 24, 1974 21 Appl. No.: 517,841

cal guide tracks each formed with a longitudinal slot at a side of the casing. Mounting members are spaced along the casing and each fixedly embraces the re- [30] Foreign Application Priority Data Nov. 7, 1973 Germany............................ 2355558 Spective guide track- A ground-engaging pp structure is carried by the mounting members and 52 US. 299/34; 299/43 p j downwardly of the bottom adjacent the [51] Int. E21C 27/35 An endless reciprocating drive Chain having an 58 Field of Search..................... 299/32, 34, 43 pp and a lower run is reeeived in the respective guide tracks, and a coal plough is located at the afore- 5 References Ci mentioned one side of the conveyor and has a rigid UNITED STATES PATENTS connecting portion which extends beneath the bottom face to the casing and is connected with the one run of the chain so that the connecting portion and the coal plough are reciprocated lengthwise of said conveyor 3,787,090 1/1974 I-Iauschopp........................... 299/43 FOREIGN PATENTS OR APPLICATIONS when the chain reciprocates in the guide tracks. The

1,380,250 10/1964 299/34 1,189,506 3/1965 Germany 299/34 Connecting portion 18 in part relieved of the weight of the conveyor and casing due to the ground- Primary Examiner-Ernest R. Purser engagement by the support structure. Attorney, Agent, or Firm-Michael S. Striker 31 Claims 8 Drawing Figures PATENTED JUL 2 91975 SHEET PATENTED JUL 2 9 I975 SHEET PATENTH] JUL 2 9 I975 SHEET SHEET PATENTED JUL 2 91975 SHEET PATENTED JUL 2 9 I975 PATENTED JUL 2 91975 SHEET SHEET PATENTEU JUL29 I975 LONG-WALL MINING APPARATUS BACKGROUND OF THE INVENTION The present invention relates generally to a mining apparatus, and more particularly to a long-wall mining apparatus.

Long-wall mining apparatus is already known in the art, for example from U.S. Pat. No. 3,458,235 (Roemer et al) and U.S. Pat. No. 3,625,567 (Blumenthal et al), to which reference may be had concerning the background and general construction of such apparatus. Apparatus of this type generally comprises an elongated conveyor which extends along a mine face from which coal is to be removed, and a coal plough that is located adjacent the conveyor to remove coal from the mine face. The coal plough is reciprocated lengthwise of the conveyor, and it is known to provide the coal plough for this purpose with a rigid extension that extends beneath the conveyor to a side thereof that is remote from the mine face, where the extension is connected with one run of a reciprocating driven chain, that is a chain which is moved to and fro in appropriate channels, to thereby move the rigid extension and the coal plough similarly to and fro lengthwise of the conveyor.

Apparatus of this type has made it possible to provide for an extremely pronounced increase in the production of coal from underground coal deposits. However, further increases in production are constantly being desired and, as it is attempted to step up the rate of production it has been found that these prior-art apparatuses have certain disadvantages which require correction. In particular, both the chain which effects movement of the coal plough and the guides which guide the chain are subject to a very significant amount of wear which becomes less and less acceptable as the rate of production of coal is being stepped up. Furthermore, the prior-art apparatuses are very noisy and it is felt highly desirable to reduce the noise level in the interest of the well-being of the operators.

Particularly the chain which effects the movement of the coal plough is subject to strong wear within the guide track, because it is in constant contact with the walls of the guide track and therefore subject to wear due to such contact. This engagement of the walls by the chain has heretofore been entirely uncontrollable, that is there has been no way of avoiding it. Furthermore, aside from the wear this behaviour of the chain has the further disadvantage of presenting a power loss for the coal plough, because a not insignificant amount of power is lost in overcoming the friction between the chain and the walls of the guide track and cannot be transmitted to the coal plough. Therefore, if the coal plough is to have a predetermined amount of power transmitted to it, it is necessary to make the drives correspondingly larger than would otherwise be necessary, so as to take into account the power loss resulting from the frictional engagement of the chain with the walls of the guide track. Other components of the apparatus are also subject to strong wear and therefore pose a constant threat to the continuous operation of the machine.

Another disadvantage of the prior art resides from the fact that if the condition of the chain is to be checked, this is associated with considerable difficulties because when the cover plate covering especially the lower one of the guide tracks is removed for inspection purposes, the chain can slip out of the guide track. The re-insertion of the chain provides substantial difficulties.

Moreover, as has been mentioned earlier this type of apparatus produces a high level of noise which is found most objectionable by the operators and by the workers who are required to be in the vicinity of the apparatus. One of the reasons for this is that the runs of the chain move completely uncontrollably in their respective guide tracks, and that the frequent frictional engagement of the chain with the walls of the guide tracks causes a high degree of noise.

Still another drawback of the prior art is that if the chain should snap as a result of wear, the ends of the chain recede relatively far in the guide track so that even when the cover of the guide track is removed it is difficult to reconnect the runs of the chain, which means that the repair of the chain under such circumstances is both costly and time consuming in itself, aside from the fact that of course during the repair period the machine is completely inoperative and does not produce coal.

SUMMARY OF THE INVENTION Accordingly, it is a general object of the invention to overcome the disadvantages of the prior art.

More particularly, it is an object of the present invention to provide an improved long-wall mining apparatus of the type in question which is not possessed of the aforementioned disadvantages.

Another object of the invention is to provide such an apparatus which operates with a substantially smaller amount of noise than those known from the prior art.

A concomitant object of the invention is to provide such an apparatus wherein the components outlined earlier are subject to much less wear than is known from the prior art apparatuses, and which apparatus therefore requires a significantly lesser frequency of repairs.

Still a further object of the invention is to provide such an apparatus in which a maximum amount of power can be transmitted to the coal plough, and the power losses resulting from friction of the powertransmitting components are substantially reduced.

In keeping with these objects, and with others which will become apparent hereafter, one feature of the invention resides in a long-wall mining apparatus which comprises an elongated conveyor adapted to extend along a mine face and having a bottom, one longitudinal side facing towards and another longitudinal side facing away from the mine face. An elongated casing is mounted on the conveyor at the other side and extends therealong upwardly of the bottom. The casing has two vertically spaced longitudinally extending cylindrical guide tracks each formed with a longitudinal slot at a side of the casing. A plurality of mounting members is spaced along the casing and each of them fixedly embraces the respective guide tracks. These mounting members extend downwardly to substantially the level of the bottom of the conveyor. A groundengaging support structure is carried by the mounting members and projects downwardly of the bottom adjacent the casing. An endless reciprocating drive chain is provided, having an upper and a lower run received in the respective guide tracks. A coal plough is located at the one side of the conveyor and has a rigid connecting portion extending beneath the bottom face to the casing where it is connected with the aforementioned one run of the chain. Thus, the connecting portion and the coal plough are reciprocated lengthwise of the conveyor when the chain reciprocates in the guide tracks, and the connecting portion is in part relieved of the weight of the conveyor and casing due to the groundengagement by the support structure.

Moreover, the chain runs are now properly guided in the respective guide tracks and have no freedom of uncontrollable movement, thus avoiding the noise and wear which previously was the result of such uncontrollable movement.

The novel features which are considered as characteristics for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a vertical cross section through an apparatus according to the present invention, illustrating one embodiment;

FIG. 1A is a perspective view, showing details of components of FIG. 1;

FIG. 1B is an exploded perspective detail, showing further components of the embodiment in FIG. 1;

FIG. 2 is a view analogous to FIG. 1, illustrating a further embodiment of the invention;

FIG. 3 is a view similar to FIG. 2, illustrating a third embodiment of the invention;

FIG. 4 is a view similar to FIG. 3, illustrating a fourth embodiment of the invention;

FIG. 5 is a view similar to FIG. 4, illustrating a fifth embodiment of the invention; and

FIG. 6 is a fragmentary plan view illustrating a detail of a component of the embodiment in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring firstly to the embodiment illustrated in FIGS. 1, 1A, 1B and 6, it will be seen that reference numeral 1 identifies an elongated conveyor which is composed of a plurality of longitudinally arrayed conveyor sections that are connected with one another so that the conveyor sections may be inclined somewhat with reference to one another both in vertical and in horizontal direction, to accommodate themselves to an uneven ground surface as well as to the contour of the mine face. Such conveyors are known from the prior art, for instance from the earlier-mentioned U.S. patents. Conveyors of this type are essentially composed of two side walls 2 which are internally profiled, and a transverse wall 3 which connects the side walls. Such conveyors are frequently constructed as scraper conveyors, having chains which are guided in the internal profiles 4 of the side walls 2 and scraper elements which in the upper run of the scraper conveyor are dragged over the upwardly directed surface of the transverse wall 3 to move coal along the latter.

The conveyor 1 has a side (in FIG. 1 the righthand side) which faces towards the non-illustrated mine face from which coal is to be moved. Reference numeral 5 identifies very diagrammatically the presence of a coal plough 5 which may be of the type disclosed in US.

Pat. Nos. 3,458,235 and 3,625,567 and which will have cutting instrumentalities that engage the mine face and remove coal therefrom when the coal plough 5 is dragged along the mine face lengthwise of the conveyor 1. The coal plough 5 is provided with a rigid extension 6 which extends beneath the conveyor 1 to the side thereof that faces away from the mine face, that is in FIG. 1 the left-hand side, for connection with an endless drive chain which is reciprocated to and fro so as to similarly reciprocate the coal plough 5 to and fro via the connecting portion 6. The portion 6 is essentially plate-shaped and may be of a plurality of plate portions arrayed in the longitudinal direction of the conveyor 1.

A mounting or compensating plate 7 is mounted at the left-hand side of the conveyor 1; it may be approximately U-shaped in cross-section and is mounted with the aid of projections 8 that extend into an outer V- shaped recess 9 of the left-hand side wall 2. Also used for mounting purposes are threaded bolts 10 which extend through keyhole-shaped cutouts in connecting portions 11 which are welded into the recess 9 in vertical orientation, so as to be flush with the outer side of the left-hand side wall 2. The height of the plate 7 corresponds substantially to the height of the side walls 2. The plate 7 is composed of a substantially L-shaped member 12 to the right-hand side of which the projections 8 are welded, and of upper and lower reinforcements 13 which are connected to the member 12 at the left-hand side, that is within the L-shaped configuration. However, it should be understood that the element 12 could also simply be planar rather than L- shaped. The reinforcements 13 are bar-shaped or stripshaped and may extend over the entire length of the plate 7 (lengthwise of the conveyor 1), but could also have a lesser length. The upper and lower reinforcements 13 may be connected with one another at spaced locations. In the region of the space 14 (see also FIG. 6) there are formed keyhole-shaped recesses 15, and in the end portions 16 of adjacent plates 7 (there is one provided for each conveyor section 1 in lengthwise direction of the latter) there are provided projections 17 to extend into respective chain links 18 which connect the projections 17 of adjacent plates 7. Splines or other components may be used for preventing undesired separation of the chain links 18 from the respective projections 17.

Mounted on the plates 7 is a channel-like casing 19 which is also subdivided lengthwise of the conveyor 1 and of itself into a plurality of sections. The casing 19 is formed with two vertically superposed cylindrical guide tracks 20 which are formed of tubular portions 21 each of which has the length of one of the sections of the casing 19 and each of which is formed with a longitudinally extending slot 22 at a side facing away from the conveyor 1. The upper and lower edges of each slot 22 are bounded with upwardly and downwardly bent wall portions 23, respectively. The lower wall portion 23 of the upper guide track 20 is welded at 23a to the upper wall portion 23 of the lower guide track 20.

The tubular portions 21 are exteriorly embraced by approximately L-shaped mounting members 24 which are distributed over the length of the casing 19. For instance, each section of the casing 19 may have three of the mounting members 24 associated with it, located at the center and the end regions of the section. The mounting members 24 are welded to the tubular portions 21 and are in turn exteriorly embraced by approximately U-shaped housing walls 25 to which they are welded. The length of the walls 25 corresponds again to the length of one of the sections of the casing 19 in each case. The long arms 26 of the walls 25 are welded to the wall portions 23, and the short arms 27 are welded to the tubular portions 21 in the regions 28 of the latter which face one another.

The housing walls 25 are formed on their outer sides facing away from the tubular portions 21 with projections 29 which engage into corresponding cutouts 30 or recesses 30 of the plate 7, as illustrated in FIG. 1B. The configuration of the mounting members 24 is most clearly seen in FIG. 1A.

Intermediate the upper and lower guide tracks 20 the housing walls 25 are formed with bores which are spaced longitudinally of the casing 19 and are identified with reference numeral 31; bolts 32 extend through the bores 31 and their heads 33 are hooked into the keyhole-shaped openings of the plate 7. When nuts 34 are then threaded onto the bolts 32, the entire casing 19 is firmly connected to the conveyor 1. Due to the presence of the centering projections 8 and the projections 29 the screw connections between the conveyor 1 and the plate 7 and between the plate 7 and the casing 19 are relieved of stresses, both horizontally and vertically. The projections 17 in conjunction with the respective chain links 18 serve to limit relative displacement of the connected components. The projections 17 may extend axially beyond the region of the space 14 and serve to center the casing 19, in which case the otherwise freely extending projections are further relieved. As a general rule the chain links 18 need not be separately secured by means of splines or the like, but such may be provided if desired. The plate 7 provides an additional abutment for an auxiliary component, such as carriage of a further coal processing machine, thereby at least partially relieving the pressures exerted by such auxiliary machine upon the casing 19.

Guide members 35 are received in the interior of the guide tracks and correspond in their cross section substantially to the cross section of the interior of the guide tracks 20. The guide members 35 are firmly but releasably mounted on the upper and lower run of the endless drive chain 36, being spaced along the respective runs. The spacing can be selected in accordance with particular requirements of a given application. The guide members 35 may be of cylindrical configuration, of barrel-shaped configuration or even of spherical configuration. It is clear that they prevent contact of the runs of the chain 36 with the inner walls bounding the guide tracks 20, thus reducing wear and noise.

The lower guide track 20 and the chain run accommodated therein also serves to guide and transmit motion to the projection 6 of the coal plough 5. For this purpose the left-hand end of the projection 6 is formed with a vertical portion 37 and an inclined portion 38 which extends through the longitudinal slot 22 of the lower guide track 20 and which is of one piece with or connected to one or more coupling portions 39 which essentially resemble the guide members 35 and are also firmly connected with the chain 36.

The left-hand side of the casing 19 is closed by a ground-engaging supporting structure 40 which has various purposes. On the one hand, it of course prevents the possibility of accidental contact of a worker with the chain 36, and the consequent possibility of injury to the worker. Furthermore, the structure is provided substantially midway of its height with connecting portions 41 via which forces exerted by not illustrated conveyor moving devices are transmitted to the casing 19 and from the same to the conveyor 1 to shift the conveyor with reference to the mine face. The lower region 42 of the structure 40 is bent leftwardly in accordance with the configuration of the portions 37 and 38 of the connecting portion 6, and the bottom end of the structure 40 is formed with a rounded groundengaging portion 43 with which it engages the ground 44. The structure 40 projects downwardly below the bottom 45 of the conveyor 1 by a distance which corresponds approximately to the vertical thickness of the portion 6, as evident from FIG. 1. This means that when the portion 6 moves below the conveyor 1 as it is being reciprocated, it need not lift the entire weight composed of the weight of the conveyor 1 and the asso ciated components, as well as the coal resting on the conveyor 1. An additional purpose of the structure 40 is to intercept possible small-dimensioned coal pieces which might slide beneath the conveyor 1 away from the mine face and towards the left in FIG. 1. Such coal pieces, usually in form of coal grains or coal dust, will tend to move upwardly after being intercepted by the structure 40 and to become lodged in the guide tracks 20 where they serve for lubricating purposes.

The hollow spaces formed between the tubular portions 21, the mounting members 24 and the housing walls 25 have the advantage that screw or bolt heads 46 can be located in them which are inserted through keyhole-shaped cutouts in the housing walls 25 and which are provided on bolts by means of which the structure 40 is connected to the casing 19; these bolts also serve to maintain in place members 47 and can serve to hold a guide 48 for an additional coal removing machine if and when such an additional machine is desired. FIG. 1 diagrammatically illustrates the possibility of providing such a machine, the base portions of which are identified with reference numerals 49 and 51 which are shown to embrace a tubular guide 50.

The aforementioned hollow spaces between the housing walls 25 and the tubular portions 21 further serve to accommodate centering bolts 52 or centering bores 53 in the end portions of the respective sections of the housing 25. FIG. 1 shows that such connections are provided so that a further centering is provided at the end portions to assure that there are smooth transitions between the guide tracks 20 formed in the respective sections of the casing 19, and no interference will occur with the movement of the guide elements 35 from the guide tracks 20 of one into those of another section of the casing.

FIG. 2 shows a further embodiment of the invention wherein like elements as in FIG. 1 have like reference numerals, such as for instance the conveyor 1, the plate 7 and the associated connecting elements.

In FIG. 2 the guide tracks 20 are again formed by tubular portions 21 of which the lower one has a longitudinally extending slot 22 which is inclined downwardly towards the ground 44 and away from the conveyor 1. The longitudinal slot 22 of the upper tubular portion 21, however, is inclined upwardly and towards the conveyor l. The tubular portions 21 are both embraced by mounting members 54 of approximately l-shaped con figuration wherein the cross bars of the I are of nonidentical length. L-shaped housing walls 55 are provided outwardly of the mounting members 54 which are spaced lengthwise of the casing 19. The end portions of the long arms 56 are connected approximately at the level of the lower respectively upper longitudinal edge 57 of the slots 22 with the shorter cross bars of the mounting members 54. The short arms 58 of the housing walls 55 are welded at 59 to the tubular portions 21. The support structure 40 in this embodiment has a straight vertical surface 60, and the members 41 are spaced vertically apart by a greater distance than in FIG. 1.

In this embodiment the connecting portion 6 of the coal plough (which latter is not shown in FIG. 2) again has the upright portion 37 but is not provided with the portion 38. Instead, it is the portion 37 itself which extends through the slot 22 of the lower guide track 20 to be connected with or of one piece with the coupling member 39 which in turn is fixedly connected with the lower run of the endless chain 36.

The upwardly facing slot 22 of the upper tubular portion 21 may be covered over, as shown in chain lines, if desired. In this embodiment it is possible to omit the portion 6 and to form the coal plough 5 with a portalshaped extension which extends above the conveyor 1 and can be connected at the ends with the chain run of the chain 36 which travels in the upper tubular portion 21. A coal breaker may also be guided on this structure and be driven by the upper run of the chain 36 with which it may be connected through the associated slot 22. Furthermore, another coal processing machine, of which the base portion 49 is shown in chain lines in FIG. 2, may be guided on the conveyor 1 may be driven by the upper run of the chain 36 through the slot 22 associated therewith. In this case, the guide 48 for such a machine 49 may be mounted on the members 47 which in turn are screw-threadedly connected to the casing 19 on the one hand and to the structure 40 on the other hand. The centering arrangements 52, 53 in this embodiment are diametrally oppositely located in the angular regions between the L-shaped housing walls 55 and the tubular portions 21.

The embodiment of FIG. 3 is also largely reminiscent of FIG. 1, and like reference numerals again identify like components. The conveyor 1, the plate 7 and the connecting elements therefor are the same as shown in FIGS. 1 and 2.

In FIG. 3 the casing 19 again has the tubular portions 21 forming the guide tracks 20. However, in this embodiment the slot 37 of the lower guide track 20 faces away from the conveyor 1 and downwardly towards the ground 44, whereas the slot 22 of the upper guide track 20 also faces away from the conveyor 1 but in upward direction. The tubular portions 21 are embraced by approximately T-shaped mounting members 61 which are spaced from one another lengthwise of the conveyor 1 and casing 19 and which abut the inner sides of a U- shaped housing wall 62 and a planar housing wall 63, respectively. The latter housing wall 63 is located at the left-hand side of the casing 19 and connects the longitudinal edges 64 bounding the upper slot 22 and the lower slot 22 at the lower and upper regions thereof, respectively. The short arms 65 of the housing wall 62 extend to the region 66 of the tubular portions 21, where they are welded to the latter. The configuration of the support structure 40 corresponds largely to that shown in FIG. 2. The centering connections 52, 53 are located in the corner regions intermediate the tubular portions 21 and the housing wall 62.

A guide 48 for an auxiliary coal mining machine may be threadedly connected to the upper region of the housing wall 62. The members 47 may be threadedly connected with the casing 19 and with the support structure 40. The end portion 37 of the projection 19 extends almost vertically through the slot 22 of the lower guide track 20.

A further embodiment of the invention is illustrated in FIG. 4, wherein the construction of the conveyor 1 corresponds to that illustrated in FIGS. 1-3. The plate 7 also is largely the same as the one shown in FIGS. 1-3, except that its height is equal to approximately 1.5 times the height of the conveyor 1, instead of being equal to that height. The connection of the plate 7 with the conveyor 1 is the same as in the preceding embodiments.

In FIG. 4 the guide tracks 20 are not formed of tubular portions 21, but instead are each composed of a pair of superposed shells 67 the concave sides of which face one another and the width of each of the shells 67 measured in circumferential direction of the respective guide track 20 corresponds approximately to one quarter of the total circumference. The shells 67 are mounted in approximately E-shaped mounting members 68, may be mounted removably therein if desired. The mounting member 68 are again spaced from one another lengthwise of the casing 19, and the width of each of the mounting members 68, of which there may for example be three provided per section of the casing 19, may be on the order of 150 mm if for instance the length of the section is 1.50 meters.

The mounting members 68 are formed with projections 29 corresponding to those and having the same purpose as the ones described with reference to FIG. 1.

The dimensions of the shells 67 in circumferential direction of the respective guide tracks 20 is sufficient to provide appropriate guidance for the guide members 35 on the chain runs of the chain 36. They also suffice to properly guide the connecting portion 6 of the coal plough (the latter is not shown) which in this embodiment again has an upwardly extending portion 38 and an inclined portion 39 which merges into or is connected with a coupling portion 39 that is secured to the lower run of the chain 36.

The support structure 40 in the embodiment of FIG. 4 is essentially the same as in FIG. 1. The mounting members 68 are formed as keyhole-shaped cutouts or depressions 69 into which the heads 46 of threaded bolts can be inserted which serve to mount the support structure 40 on the mounting members 68, and which can also serve to connect the members 47 to the mounting members 68 and to the plate 7. The latter may be provided in the upper region at the inwardly facing side with a reinforcement bar or portion 71 which serves as an abutment for the mounting member 68. The outer side of the plate 7 may be provided with a guide 48 for the base 49 (diagrammatically shown) of an auxiliary coal processing machine.

The embodiment in FIG. 5, finally, differs from that of FIG. 4 in that the shells 67 of the lower guide track 20 are not vertically superposed with reference to one another, but are offset through approximately 30 in counterclockwise direction with reference to the vertical so that the slot 22 of the lower guide track 20 through which the upwardly extending portion of the connecting portion 6 extends, is inclined downwardly and away from the conveyor 1. It is clear from FIG. that this makes it possible for the upwardly extending portion of the connecting portion 6 to extend almost vertically through the slot 22 into the guide track 20. Moreover, the side 60 of the support structure 40 which faces towards the guide tracks can thus be planar in vertical direction, instead of having to be shaped as for instance shown in FIG. 1. In other respects the embodiment of FIG. 5 corresponds to that of FIG. 4.

The improved apparatus according to the present invention has manifold advantages. Because of the particular manner in which the runs of the chain 36 are now guided in the guide tracks 20, wear due to engagement of the chain with the walls bounding the guide track becomes virtually non-existant, and similarly the noise level resulting from such engagement is eliminated. Furthermore, the power losses resulting from the necessity for the drive to overcome the friction resulting from such engagement, are eliminated so that all of the power can now be transmitted to the coal plough 5 to reciprocate the latter. The guidance of the portion 6 and thereby the coal plough 5 is now exclusively a matter of the guide track into which the coupling portion 39 extends.

In the event there should be a breakage of the chain 36, the broken ends will not be able to recede from one another lengthwise of the associated guide track, and they will not be able to fall out of the guide track so that the support structure 40 now is no longer required to perform the function of previous covering plates which were provided for this purpose over the guide tracks, but can act as a true support structure which can project downwardly below the bottom face of the conveyor 1 and can support the entire apparatus at the lefthand side (in the illustrated embodiments), so that the projection or plate 6 no longer needs to lift the entire weight of the apparatus plus the weight of the coal on the conveyor 1, as it passes beneath the latter during its reciprocation. This of course also contributes to a better transmission of the power of the drive to the coal plough 5.

In the event that a breakage of the chain 36 should in fact occur, it is no longer necessary to insert the reconnected end portions with great difficulty into the guide tracks, as was required in the prior-art constructions. The end portions of the chain can be readily inserted through the slots 22 into the guide track, the guide elements 35 placed onto them, and the end portions 3 then be reconnected. Moreover, because of the presence of the guide elements 35 the free end portions of the chain, which result if the chain should break, will not be able to recede very far from one another, being prevented therefrom by the presence of the guide elements 35.

Due to the manner in which the tubular portions 21 or the shells 67 can be mounted by the respective mounting members, they are firmly held and forces, particularly those resulting from external equipment used to shift the apparatus via the structure 40 and its portions 41 relative to the mine face, are transmitted directly into the plate 7 and to the conveyor 1.

The dimensioning of the slots 22 is such that on the one hand an undesired movement of the guide elements 35 or coupling elements 39 outwardly through these slots 22 is reliably prevented, but on the other hand ready access to the interior of the guide tracks 20 and to the chain 36 is assured for repair or replacement of various components. The tubular portions 21 or the shells 67 can be produced inexpensively and in a very simple manner, and because of the way in which they are mounted on and by the mounting means, the resistance of the structure to bending or other deformation is so great that no such damage can occur during the operation of the machine. Where the wall portions bounding the slots 22 in the tubular portions 21 are bent outwardly in upward or downward direction, as are the wall portions 23 in FIG. 1, this eliminates sharp edges bounding the slots 22 and the possibility of injury to an operator or damage to components that might come in contact with such edges. In those embodiments, such as in FIG. 2, where the slot 22 of the upper tubular portion 21 faces upwardly and towards the conveyor 1, another type of machine can be connected with the upper run of the chain 36 through this slot 22, to be reciprocated by the chain if and when desired. As pointed out earlier, if no use is to be made of this possibility, then this slot can be covered over as shown in chain lines in FIG. 2.

It should be understood that conveyors such as the conveyor 1 in a typical long-wall mining apparatus will have a length of approximately -200 meters, whereas the length in the same direction of the coal plough 5 and its plate-like connecting portion 6 will be approximately 6 meters. This means that wherever the portion 6 moves beneath the conveyor 1 it has to lift the same up, and the conveyor 1 will drop back to engagement with the ground when the projection 6 has moved away lengthwise of the conveyor 1. This movement is facilitated in the apparatus according to the present invention because of the support of the apparatus on the ground 44 by the portion 43 of the support structure 40, since the entire apparatus can in effect tilt in counterclockwise direction at those locations where the projection 6 happens to be located, whereas at longitudinally spaced locations the apparatus will tilt slightly downwardly in clockwise direction about the portion 43 under the weight of the conveyor 1 and any coal that may be located on the same. It will also be understood that at each of the opposite ends of the apparatus there will be located a drive which effects the reciprocation of the chain 36; such drives are well known from the art, and are for instance disclosed in the aforementioned U.S. patents.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in a long-wall mining apparatus, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.

What is claimed as new and desired to be protected by letters Patent is set forth in the appended claims.

1. In a long-wall mining apparatus, a combination comprising an elongated conveyor adapted to extend along a mine face and having a bottom, one longitudinal side facing towards and another longitudinal side facing away from said mine face; an elongated casing, mounted on said conveyor at said other side and extending therealong upwardly of said bottom, said casing having two vertically spaced longitudinally extending cylindrical guide tracks each formed with a longitudinal slot at a side of said casing; a plurality of mounting members spaced along said casing and each fixedly embracing the respective guide tracks, said mounting members extending downwardly to substantially the level of said bottom; a ground-engaging support structure carried by said mounting members and projecting downwardly of said bottom adjacent said casing; an endless reciprocating drive chain having an upper and a lower run received in the respective guide tracks; and a coal plough located at said one side of said conveyor and having a rigid connecting portion extending beneath said bottom face to said casing and connected with one run of said chain, so that said connecting portion and coal plough are reciprocated lengthwise of said conveyor when said chain reciprocates in said guide tracks, and said connecting portion is in part relieved of the weight of said conveyor and casing due to the ground-engagement by said support structure.

2. A combination as defined in claim 1, wherein said conveyor and casing are composed of longitudinally ar rayed sections.

3. A combination as defined in claim 1, wherein said connecting portion has a given thickness in vertical direction; and wherein said support structure projects downwardly beyond said bottom by a distance substantially equal to said given thickness.

4. A combination as defined in claim 1, wherein said connecting portion has a free end received in and contoured to the interior cross-section of one of said guide tracks, said free end being connected with said one run of said chain.

5. A combination as defined in claim 1, wherein said guide tracks are constituted by tubular portions of said casing, said tubular portions being formed at one side with said slots and at the opposite side being embraced by said mounting members.

6. A combination as defined in claim 5, wherein said slots have a width in circumferential direction of the respective tubular portion which is equal to slightly less than one quarter of the total circumference of the respective tubular portion.

7. A combination as defined in claim 5, wherein said side of said casing faces away from said conveyor.

8. A combination as defined in claim 7, wherein said mounting members are of substantially C-shaped outline.

9. A combination as defined in claim 7, wherein each of said tubular portions has marginal wall portions extending along the associated slot and being respectively bent upwardly and downwardly therefrom.

10. A combination as defined in claim 9, wherein one of said tubular portions is located above the other tubular portion; and wherein the upwardly bent marginal wall portion of said other tubular member is welded to the downwardly bent marginal wall portion of said one tubular portion.

11. A combination as defined in claim 9, wherein said casing comprises a substantially C-shaped housing having substantially horizontal upper and lower walls; and wherein said upwardly bent marginal wall portion of an upper one of said tubular portions is welded to said upper wall, and the downwardly bent marginal wall portion of a lower one of said tubular portions is welded to said lower wall.

12. A combination as defined in claim 5, wherein one of said tubular portions is located above the other tubular portion; and wherein the slot in said one tubular portion faces upwardly and in direction toward said one longitudinal side of said conveyor, and the slot in other tubular portion faces downwardly and in direction away from said longitudinal sides of said conveyor.

13. A combination as defined in claim 5, wherein said casing comprises a housing composed of two sidewalls of substantially L-shaped and inverted L-shaped crosssection, respectively; and said mounting members have substantially a horizontally arranged double-T shaped form and are provided with end flanges at least one of which is welded to said sidewalls.

14. A combination as defined in claim 13, wherein one of said sidewalls is welded to an upper one of said tubular portions at the level of a lower edge of said slot therein, and the other of said sidewalls is welded to a lower one of said tubular portions at the level of an upper edge of said slot therein.

15. A combination as defined in claim 1, wherein said slots both face away from said conveyor and the lower slot is inclined downwardly whereas the upper slot is inclined upwardly.

16. A combination as defined in claim 1, wherein said casing comprises a housing composed of two sidewalls which are respectively of substantially C-shaped and planar configuration; and wherein said mounting members have substantially a horizontally arranged double- T shaped form and are provided with end flanges which are welded to the respective housing walls.

17. A combination as defined in claim 16, wherein said C-shaped housing wall has an upper and a lower substantially horizontal wall portion; and wherein said guide tracks comprise an upper tubular portion provided with one of said slots and being welded to an underside of said upper horizontal wall portion, and a lower tubular portion provided with the other of said slots and being welded to an upper side of said lower horizontal wall portion.

18. A combination as defined in claim 16, said planar sidewall facing said slots and having an upper longitudinal edge portion and a lower edge portion; wherein said guide tracks comprise an upper and a lower tubular portion each provided with one of said slots; and wherein said upper longitudinal edge portion is welded to said upper tubular portion in the region of a lower edge of said slot therein, and said lower edge portion is welded to said lower tubular portion in the region of an upper edge of said slot therein.

19. A combination as defined in claim 1, wherein each of said tracks is composed of a pair of elongated shells of part-circular cross-section which are located opposite one another and define with one another a respective slot.

20. A combination as defined in claim 19, wherein said mounting members are of substantially E-shaped configuration and have an upright backwall which faces towards said conveyor.

21. A combination as defined in claim 20, wherein said shells of the respective tracks have concave sides facing one another, one shell of each track being located vertically above the other shell of the same track; and wherein said mounting members each have three substantially horizontal vertically spaced arms projecting from said backwall and having the respective shells secured thereto.

22. A combination as defined in claim 20, wherein said shells of an upper one of said tracks are vertically superposed and have concave sides which face one another; and wherein the shells of a lower one of said tracks are also superposed and have concave sides which face another, said shells of said lower track being offset from the vertical in counterclockwise direction by substantially 30.

23. A combination as defined in claim 1; and further comprising a substantial! U-shaped connecting element connecting said casing with said conveyor.

24. A combination as defined in claim 23, wherein said connecting element is formed with openings; and wherein said mounting members are provided with projections which extend into said openings.

25. A combination as defined in claim 23, wherein said casing is formed intermediate said guide tracks with a plurality of longitudinally spaced bores, and said connecting element is formed with keyhole-shaped openings; and further comprising bolts anchored in said bores and releasably received in the respective keyhole-shaped openings.

26. A combination as defined in claim 1, said casing including a housing having spaced end regions; and further comprising centering means at said end regions for centering said guide tracks with reference to said housing.

27. A combination as defined in claim 1, wherein said mounting members are formed with openings for connection of auxiliary components thereto.

28. A combination as defined in claim 1; and further comprising a substantially U-shaped connecting element connecting said casing with said conveyor and having in vertical direction a height which corresponds substantially to that of said conveyor.

29. A combination as defined in claim 1; and further comprising a substantially U-shaped connecting element connecting said casing with said conveyor and having in vertical direction a height which is equal to substantially 1.5 times the height of said conveyor.

30. A combination as definedin claim 1, wherein said conveyor, said casing and said connecting element are each composed of a plurality of longitudinally arrayed sections; and wherein each section of said connecting element has spaced end regions provided with projections which project towards said conveyor and serve for connecting said section of said connecting element to a respective longitudinally adjacent section of the same.

31. A combination as defined in claim 1, wherein said support structure includes an upright plate having a lower end portion which engages the ground and is bent over in direction away from said conveyor. 

1. In a long-wall mining apparatus, a combination comprising an elongated conveyor adapted to extend along a mine face and having a bottom, one longitudinal side facing towards and another longitudinal side facing away from said mine face; an elongated casing, mounted on said conveyor at said other side and extending therealong upwardly of said bottom, said casing having two vertically spaced longitudinally extending cylindrical guide tracks each formed with a longitudinal slot at a side of said casing; a plurality of mounting members spaced along said casing and each fixedly embracing the respective guide tracks, said mounting members extending downwardly to substantially the level of said bottom; a ground-engaging support structure carried by said mounting members and projecting downwardly of said bottom adjacent said casing; an endless reciprocating drive chain having an upper and a lower run received in the respective guide tracks; and a coal plough located at said one side of said conveyor and having a rigid connecting portion extending beneath said bottom face to said casing and connected with one run of said chain, so that said connecting portion and coal plough are reciprocated lengthwise of said conveyor when said chain reciprocates in said guide tracks, and said connecting portion is in part relieved of the weight of said conveyor and casing due to the groundengagement by said support structure.
 2. A combination as defined in claim 1, wherein said conveyor and casing are composed of longitudinally arrayed sections.
 3. A combination as defined in claim 1, wherein said connecting portion has a given thickness in vertical direction; and wherein said support structure projects downwardly beyond said bottom by a distance substantially equal to said given thickness.
 4. A combination as defined in claim 1, wherein said connecting portion has a free end received in and contoured to the interior cross-section of one of said guide tracks, said free end being connected with said one run of said chain.
 5. A combination as defined in claim 1, wherein said guide tracks are constituted by tubular portions of said casing, said tubular portions being formed at one side with said slots and at the opposite side being embraced by said mounting members.
 6. A combination as defined in claim 5, wherein said slots have a width in circumferential direction of the respective tubular portion which is equal to slightly less than one quarter of the total circumference of the respective tubular portion.
 7. A combination as defined in claim 5, wherein said side of said casing faces away from said conveyor.
 8. A combination as defined in claim 7, wherein said mounting members are of substantially C-shaped outline.
 9. A combination as defined in claim 7, wherein each of said tubular portions has marginal wall portions extending along the associated slot and being respectively bent upwardly and downwardly therefrom.
 10. A combination as defined in claim 9, wherein one of said tubular portions is located above the other tubular portion; and wherein the upwardly bent marginal wall portion of said other tubular member is welded to the downwardly bent marginal wall portion of said one tubular portion.
 11. A combination as defined in claim 9, wherein said casing comprises a substantially C-shaped housing having substantially horizontal upper and lower walls; and wherein said upwardly bent marginal wall portion of an upper one of said tubular portions is welded to said upper wall, and the downwardly bent marginal wall portion of a lower one of said tubular portions is welded to said lower wall.
 12. A combination as defined in claim 5, wherein one of said tubular portions is located above the other tubular portion; and wherein the slot in said one tubular portion faces upwardly and in direction toward said one longitudinal side of said conveyor, and the slot in other tubular portion faces downwardly and in direction away from said longitudinal sides of said conveyor.
 13. A combination as defined in claim 5, wherein said casing comprises a housing composed of two sidewalls of substantially L-shaped and inverted L-shaped cross-section, respectively; and said mounting members have substantially a horizontally arranged double-T shaped form and are provided with end flanges at least one of which is welded to said sidewalls.
 14. A combination as defined in claim 13, wherein one of said sidewalls is welded to an upper one of said tubular portions at the level of a lower edge of said slot therein, and the other of said sidewalls is welded to a lower one of said tubular portions at the level of an upper edge of said slot therein.
 15. A combination as defined in claim 1, wherein said slots both face away from said conveyor and the lower slot is inclined downwardly whereas the upper slot is inclined upwardly.
 16. A combination as defined in claim 1, wherein said casing comprises a housing composed of two sidewalls which are respectively of substantially C-shaped and planar configuration; and wherein said mounting members have substantially a horizontally arranged double-T shaped form and are provided with end flanges which are welded to the respective housing walls.
 17. A combination as defined in claim 16, wherein said C-shaped housing wall has an upper and a lower substantially horizontal wall portion; and wherein said guide tracks comprise an upper tubular portion provided with one of said slots and being welded to an underside of said upper horizontal wall portion, and a lower tubular portion provided with the other of said slots and being welded to an upper side of said lower horizontal wall portion.
 18. A combination as defined in claim 16, said planar sidewall facing said slots and having an upper longitudinal edge portion and a lower edge portion; wherein said guide tracks comprise an upper and a lower tubular portion each provided with one of said slots; and wherein said upper longitudinal edge portion is welded to said upper tubular portion in the region of a lower edge of said slot therein, and said lower edge portion is welded to said lower tubular portion in the region of an upper edge of said slot therein.
 19. A combination as defined in claim 1, wherein each of said tracks is composed of a pair of elongated shells of part-circular cross-section which are located opposite one another and define with one another a respective slot.
 20. A combination as defined in claim 19, wherein said mounting members are of substantially E-shaped configuration and have an upright backwall which faces towards said conveyor.
 21. A combination as defined in claim 20, wherein said shells of the respective tracks have concave sides facing one another, one shell of each track being located vertically above the other shell of the same track; and wherein said mounting members each have three substantially horizontal vertically spaced arms projecting from said backwall and having the respective shells secured thereto.
 22. A combination as defined in claim 20, wherein said shells of an upper one of said tracks are vertically superposed and have concave sides which face one another; and wherein the shells of a lower one of said tracks are also superposed and have concave sides which face another, said shells of said lower track being offset from the vertical in counterclockwise direction by substantially 30*.
 23. A combination as defined in claim 1; and further comprising a substantiall U-shaped connecting element connecting said casing with said conveyor.
 24. A combination as defined in claim 23, wherein said connecting element is formed with openings; and wherein said mounting members are provided with projections which extend into said openings.
 25. A combinAtion as defined in claim 23, wherein said casing is formed intermediate said guide tracks with a plurality of longitudinally spaced bores, and said connecting element is formed with keyhole-shaped openings; and further comprising bolts anchored in said bores and releasably received in the respective keyhole-shaped openings.
 26. A combination as defined in claim 1, said casing including a housing having spaced end regions; and further comprising centering means at said end regions for centering said guide tracks with reference to said housing.
 27. A combination as defined in claim 1, wherein said mounting members are formed with openings for connection of auxiliary components thereto.
 28. A combination as defined in claim 1; and further comprising a substantially U-shaped connecting element connecting said casing with said conveyor and having in vertical direction a height which corresponds substantially to that of said conveyor.
 29. A combination as defined in claim 1; and further comprising a substantially U-shaped connecting element connecting said casing with said conveyor and having in vertical direction a height which is equal to substantially 1.5 times the height of said conveyor.
 30. A combination as defined in claim 1, wherein said conveyor, said casing and said connecting element are each composed of a plurality of longitudinally arrayed sections; and wherein each section of said connecting element has spaced end regions provided with projections which project towards said conveyor and serve for connecting said section of said connecting element to a respective longitudinally adjacent section of the same.
 31. A combination as defined in claim 1, wherein said support structure includes an upright plate having a lower end portion which engages the ground and is bent over in direction away from said conveyor. 